It is very important to consider how you are using JavaScript on your websites and think about how to mitigate any performance issues that it might be causing. While images and video account for over 70% of the bytes downloaded for the average website, byte per byte, JavaScript has a greater potential for negative performance impact — it can significantly impact download times, rendering performance, and CPU and battery usage. This article introduces tips and techniques for optimizing JavaScript to enhance the performance of your website....is — when you have a large chunk of HTML to add to the page,...a separate thread to run a chunk of JavaScript in, so that it...